What are the differences between the JPG format and the PNG format? Both formats are widely used in web environments, but each one has a series of particularities that make them suitable for different purposes. The main difference is that the PNG format allows you to save transparencies thanks to its alpha channel, but there are other characteristics of these two formats that will help you choose the best option.
Size and quality
Before going into this aspect in depth, it is necessary to be clear that the JPG format is a format that entails a loss of quality each time it is saved, while the PNG format is a lossless format.
When we work with an image in PNG format which we clearly differentiate the number of colors, such as an illustration with flat colors, the seize will be significant less than JPG with the same quality.
This is best seen in the following example:
As we can see to obtain a good quality of the image the most optimal result is given by the PNG-8 format, with a weight 4 times less than in JPG format.
Difference between PNG-8 and PNG-24 formats
The difference between PNG-8 and PNG-24 lies in the colour depth for each channel (if we work in RGB mode the image will have 3 channels: Red – Green – Blue).
With the PNG-8 format we limit the number of colours to 256. For the image we are using as a sample it is more than enough, however on other occasions it will be better to use the PNG-24 format as we have up to 16.7 million colours available.
On the other hand, for photographs where it is impossible to count the number of spot colours, as it would be a huge amount, the best option is to choose the JPG format, the PNG format would be very heavy.
Let’s look at an example:
In this case the PNG-8 option would be unfeasible, as reducing the colour limit to 256 colours would significantly affect the quality of the image.
Banding and bits in jpg and png formats
Banding is the effect produced when making a simple gradient where stripes of different shades appear causing a discontinuous gradient. If you work with photo editing or illustration tools such as Photoshop or Illustrator you may have encountered this problem and did not know why, the answer is in the bits.
If you need to convert a file in jpg format to png format it is as simple as using a file converter like PDF Converter, always taking into account the technical aspects that we have discussed above and its final use.
As we talked about before, the PNG format can contain 8 or 24 bits of depth that establishes the amount of colours plus an extra channel (alpha channel) of transparency. If we work with an image of 8bits of depth we do not have a sufficiently high range of colours to obtain a fluid gradient, hence we find the banding effect, however, from 16bits onwards this effect is notably reduced.
In jpg format files we cannot work with more than 8bits of depth, so we must work with other formats, such as PNG, which supports up to 32bits of depth. There are also other formats such as EXR, which is more commonly used for photo editing.
Therefore, if we need to edit an image, it is better to work with a format that allows us to store 16bits per channel, in order to have a wider range of tonalities.
We hope that with this information you will be clearer about when to choose one format or another, depending on the needs of your project, whether it is for a digital image or if you are working on a print project.